Toy airplane



M. PALMER.

TOY AIRPLANE.

APPLICATION FILED MAR.12, 1920. I

1,359, 19. Patented Nov. 23, 1920.

2 SHEETS-SHEET I.

ATTORNEY M. PALMER.

Patented Nov. 23, 1920.

2 SHEETS-SHEET 2.

ATTORNEY UNITED STATES MONTAGUE PALMER, OF NEW YORK, N. Y., A'SSIGNOR TOIDEAL SUPPLY COMPANY, OF NEW/V YORK, N. Y.

PATENT OFFICE...

annormnn &

1.3 TOY AIRPLANE.

Specification of Letters Patent.

Patented Nov. 23, 1920.

Application filed March 12, 1920. Serial No. 365,290.

T 0 all whom it may concern:

Be it known that I, MONTAGUE PALMER, a citizen of the United States, andresident of the borough of Bronx, in the cit county, and State of NewYork, have invented certain new and useful Improvements in ToyAirplanes, of which the following is a specification.

This invention relates to model or toy airplanes, and my improvementsare directed to certain novel characteristic features in the attachmentof the aerofoils to the frame, whereby also the aerofoils are accorded adesired camber and angle of incidence, together with novel propellerfitting means and connecting devices for the propeller power element.

Therefore my invention consists of a frame element in the form of asingle longeron that is rectangular in cross section, a main supportingaerofoil composed of spring-like sheet material, such as fiber, sprungto a chord-wise curvature or camber, and pierced with centrally alinedorifices by which it is strung along said longeron, whereby the sprungand curved formation of said aerofoil is maintained inthe attachedrelation between the aerofoil and its longeron; and said aerofoil havingits leading edge reinforced through a folded back portion that stifi'enssaidedge and permits some cavitation to occur and thus enhance theaerodynamical effect in flight.

The small forward aerofoil or elevator in.

this model or toy machine is similarly attachable to the longeron, butthe longeron en gaging orifices therein are differently provided,because with the elevator it isnecessary to provide a set angle ofincidence therefor. Thus the forward orifice is formed in a pendent tabor lug, which comes into a inement with a rearward orifice through theaerofoil when the latter is sprung into the desired cambered shape,thereby also according the elevator aerofoil the requisite angle ofincidence whereby the device will be caused to ascend in its flight.

The propeller, in a single propeller machine, is revolubly mounted inthe hanger portion of a socket fitting that fits over the rear end ofthe longeron, and a hook that compri es the terminal portion of thepropeler shaft, engages the elastic-power band that also engages a hookfitting carried by alon said lon eron the front end of the longeron.This latter hook fitt ng also has a hook like portion whose point entersan axial hole therefor in the longeron end, while the shank portionthereof lies in a longitudinal slot in the longeron end to secure thefitting from turning under the twisting tension of the power band.

Also, for a two propeller machine I provide a transverse member of stifimaterial,

like sheet metal, having alined orifices to centrally thereof receivethe rear end portion of the longeron, and the opposite lateral cues ofsaid member having bearings for I the shaft of the respectivepropellers; the forward engaging means for the respective power bandscomprising a double hook whose v shank lodges in an endwise slot in theforward end of the longeron.

Other features and advantages of my said invention will hereinafterappear.

Figure 1 is a plan view of my invention as applied to a single propellermodel airplane.

Fig. 2 is aside sectional view, taken on the line 2-2 of Fig. 1.

Fig. 3 is an enlarged detail sectional view taken on the line 3-3 ofFig. 1. 7 vi Fig. 8* is a section on the line S -3 of 1* lg. 1.

Fig. 3 is a section on the line 3 3 of Fig. 1. I y

Fig. 4 is a plan view of my invention as applied to a two propellermodel airplane.

Fig. 5 is an enlarged section on the line 55 of Fig. 1. 1 a

Fig. 6 is an enlarged section on the line 6-6 of Fig.

Fig.7 is an enlarged section on the line ?'-.7 of Fig. 4, and V Fig-f7is a section on theline 7-7 of Fig. 7. y

InFigs. 1 and 2 I have shown a frame portion composed of a singlelongeron 1', rectangularin crosssection, and of equal cross-sectionalarea throughout. Strung at suitable distances apart, are the aerofoils 2and 3, of which t 1e aerofoil 2 comprisesthe main supporting unit of themodelairplane, and 3 an auxiliary or elevator unit. Said aerofois may becomposed of spring-like sheet material, such-as fiber, hough obviouslyother ma:

terial ofsuirable naturemay be used.

The aerofoil '2 is provided with the rect angular orifices l, 4, and,assuming said aerofoil to have been curved or sprung into thecambered-like curvature indicated in Fig. 2, then said orifices 4t, 4,which are in ahnement centrally of the aerofoll span,

admit the reception of longeron 1, that is passed therethrough above theleading and trailing edges of said aerofoil and beneath the centralportion of its material lying between said orifices, whereby saidlongeron,

. through the tension of the aerofoil, as

sprung, localizes the latter in a set position relatively to thelengthof the longeron, and

ture and distortion.

engagement of the aeroioil with tl e longeron.

about its longitudinal axis in the. direction.

of propeller rotation, I may provide the aerofoll, at that wing sidewhich would be pressed downwardly, with a warped portion such as at 7 toresist such. turning tendency. v

The elevator aerofoil 3 is applied to longeron 1 in a manner slmilar toaerofo1l2 to impart camber thereto, excepting that only one orifice 8isprovided in the aerofoil, bein located centrally of the span thereofant near its trailing edge, a complementary orifice 9 however beingformed in a forwardly pendent tab or lug 1O atthe leading edge of saidaerofoil, so that thereby the said leading edge is elevated above thelongitudinal plane of the longeron and a desired set angle of incidenceis accorded said aerofoil, to enable it to function as an elevator.

The singlepropeller 11 employed with this type of model airplane isapplied thereto as by a fitting 12, which comprises a strip of metalhaving the arms 13 folded to form a rectangular'socket to receive thelongeron end portion, and an arm 14 that is folded against the socket tocomprise an end closure therefor, and also to serve as an abutment wallor stop for the longeron end,

said arm extending below the socket and there having an orifice 15 toserve as a bearing for the propeller shaft 16. As is usual, this shaft16 consists ofa piece of wire that is wrapped at one end 17 about thecentral portion oft-he propeller, and at its other end terminatesin ahook 18 for engagement with a power band 19.

' I provide however ,a novel form of thrust hearing which consists ofone or more per forated metal beads 'strnng' along shaft a folded underpor 16 and interposed between the arm 14 and the junction or hub likeportion of wire end 17.

A fitting 21 at the forward end of longeron 1 has the hook portion 22 toengage the power band, and a reverse hook 23 whose pointed end engagesin an axial orifice therefor in t 1e longeron end, while an end slot 24;in said longeron, adjoining said orifice, receives the shank portion ofhook 23 and thereby localizes fitting 21, precenting it from rotatingunder the twist tension of the power band g The example of my inventionshown in Fig. 41-, which relates to a two-propeller model airplane, haslongeron 25 with aero-- foils 26 and 27 that'correspond in theiressential characteristics respectively with the aerofoils 2 and 3, as totheir camber, and

means of attachment to said longeron, and

differ from the device ofliig, 1 in that the rear end or fitting 1s mthe form of a transverse member 27*,here shown as a strip of metal,whose rear portion is folded under to produce the rectangular structure28, having a central, squared. orifice 29 to receive the rear portion ofthe longeron whose end butts a ainst the rear wall of structure 28-saidstructure also having a downwardly inclined portion 30 with a centralrectangular orifice 31 toadmit the receptlon of the longeron andlocalizethe latter and said structure having n its vertical rear wall,equrspaced from the center thereof, orifices 32, 32,wh1ch respectivelyserve as bearings fol-the shafts 83, 33 of the oppositely rotatablepropellers 34:, 34 The shafts 33, 33 each have a hook 34ltoengage-separate powerbands 35 for the operation of the propellers, saidbands 35 respectively engaging with a forward fitting of novelcharacter. In effect said fitting comprises a U shaped wire member 36which is lodged against rotation in a slot 87 provided in thelongeronforward end, the opposite ends of member 36 terminating in books38, 38,.that respectively engage said power bands. i

In the example of Fig.4, the forward orifice 27 is shown asbeing'formedpartly in the extension 27 of aerofoil27, but located so as to permitthe leading edge of said aerofoil tohave a set angle of incidence.

It willbe obvious that if the reception orifices in the aerofoil. forthe longeron are symmetrical with the transverse axis of said aerofoilthen camber will be provided there in'with a zero angle of incidence,but if the.

orifices are advanced relatively tothe aerofoil, then camber will be.provided with positive angle of incidence. g

In some cases where 1t s desirable for (11s the "longeron', as at 1 inFig. 1, then I provide a sleeve 1* asst aluminum, to unite the e m mbe-vise .lees 'ei f s vic r assembling purposes to break the length ofVariations may be resorted to within the spirit and scope of myinvention and parts thereof used without others.

I claim: a

1. A demountable toy airplane comprising an aerofoil of spring-likesheet material, having orifices through its span center, in chord-wisespaced alinement when said aerofoil is sprung in cambered form, and alongeron to engage said orifices and maintain the cambered form of saidaerofoil in its attached relation to said longeron. it

2. In a demountable toy airplane having a longeron comprising its frame,an elevator aerofoil of spring-like sheet material, having a rearwardorifice through its span center, a forward pendent extension or tabhaving an orifice, said orifices being alined when the aerofoil issprung in cambered form, and said longeron serving to engage saidorifices to maintain the cambered form of said aerofoil and impart a setangle of incidence thereto in its attached relation to saidlongeron.

3. In a demountable toy airplane having a longeron comprising its frame,an elevator aerofoil of spring-like sheet material, having a rearwardorifice through its span center, and a forward orifice, said orificesbeing alined when the aerofoil is sprung in cambered form, and saidlongeron serving to engage said orifices to maintain the camber-ed formof said aerofoil and impart a set angle of incidence thereto in itsattached relation to said longeron.

4. In a toy airplane, in combination, a longeron having an axial orificein one end thereof, and a vertical slot extending from said orifice tothe under surface of said longeron, a fitting comprising a member havingopposite hook portions, whereof one hook portion serves to engage apower band, and the other hook is engageable in said axial orifice, theshank of said fitting being engageable with said slot to prevent turningof said fitting under the twist tension of the power band.

5. In a toy airplane having a longeron, two propellers, shafts therefor,and power bands engageable with said shafts, the combination of afitting composed of stiff, sheet material, folded to form a transverserec= tangular hollow structure, with a forwardly inclined portion, thefront wall of said structure and said inclined portion having alinedorifices to receive the end portion of the longeron, and the rear wallof said structure comprising an abutment terminal for said longeron end.

6. In a toy airplane having a longeron, two propellers, shafts therefor,and power bands engageable with said shafts, the combination of afitting composed of stifi', sheet material, folded to form a transverserectangular hollow structure, with a forwardly inclined portion, thefront wall of said structure and said inclined portion having alinedorifices to receive the end portion of the longeron, the rear wall ofsaid structure comprising an abutment terminal for said longeron end,and the lateral portions of said fitting having bearing orifices for thepropeller shafts.

'7'. In a toy airplane, in combination, a longeron having a transverseslot at one end, said slot opening into grooves at the opposite sides'ofsaid longeron, two propellers mounted at the opposite end of saidlongeron, a power band for each propeller, and a U-shaped wire fittingengageable in said slot and grooves, said fitting having oppositeterminal hooks for respective engagement with said power bands.

Signed at the borough of Manhattan, in the city, county and State of NewYork this 10th day of March, A. D. 1920.

MON TAGUE PALMER.

